AME, Inc.
AME5134
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General Description
The AME5134 drives white LEDs in series with a con-
stant current to provide efficient display backlighting in
cellular phones, PDAs and other hand-held devices. The
step-up converter includes an internal 30V, low R
DSON
, N-
channel MOSFET switch for high efficiency and maxi-
mum battery life.
To control LED brightness, the LED current can be
pulsed by applying a single analog/PWM signal with a
frequency range of 100Hz to 10 KHz to the control
pin(CTRL). A separate enable input provides on/off con-
trol. Soft-start minimizes inrush current during start up.
The AME5134 is available in space-saving DFN-8 (3mmx
3mmx0.75mm) package.
High-Efficiency, 30V Boost
Converters for 2 to 6 White LEDs
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Applications
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Cellular Phones
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PDA, Palmtop, and Wireless Handhelds
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Color Display Backlight
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Features
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Constant-Current Regulation for LED
IIIumination
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Internal 30V MOSFET Switch Capable of
Driving 6LEDs
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Small, Low-Profile External Components
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2.7V to 5.5V Input Range
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Up to 88% Efficiency Driving 6 LEDs
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Precise Brightness Control Using PWM
Signal or Analog Signal
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Optimized for Low Input Ripple
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Soft-Start to Minimize Inrush Current
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DFN-8 (3mmx3mmx0.75mm) Package
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All AME's Lead Free Products Meet RoHS
Standard
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Typical Application
L1
47µH
V
IN
2.7V to 5.5V
C1
4.7µF
C2
0.47µF
R1
200KΩ
V
IN
ON
OFF
EN
SW
OV
R2
10KΩ
C4
4700pF
AME5134
PWM
OR
DC Control
CTRL
SS
FB
GND
R3
10Ω
C3
0.1µF
Rev.C.01
1
AME [ ANALOG MICROELECTRONICS ]
